Step



W. A. MITCHELL. STEF- APPLICATION FILED JAN. so. 1922.

1,436,281 Patented Nov. 2l, 1922.

l y www i Patented Nov. 2l, 1922.

Mdm@

WILLIAM A. MITCHELL OF DENISON, TEXAS.

STEP.

Application filed January 30, 1922.

T 0 @ZZ ev hom. t may concern Be it known that I, WILLIAM A. MITCHELL, acitizen of the United States', residing at Denison, in the county ofGrayson and State o-f Texas, have invented `a certain new and usefulImprovement in Steps, vof which the following is a full, clear, concise,and exact description, reference being had to the accompanying drawings,forming a part of this specification.

This invention relates `to vimprovements in steps.

The `object of the invention is to provide a durable, strong and safestep or stairs particularly adapted for application to railway passengerequipment.

In the drawing `forming a part of this specification, Figure l is a.vertical, sectional view of a car step showing Vmy improvements inconnection therewith. Figure '2 is a top plan view, upon an enlargedscale, of one of the treads employed in the step. And Figure 3 is atransverse, sectional view corresponding substantial-ly to the line 3--3of Figure 2 and on a somewhat larger scale.

In said drawing, one of the sta-ir stringers is indicated at l0, thesame being of suitable shape and preferab-ly of sheet metal and withthev outer exposed edge covered by a strip ll. The step or stairway asshown is provided with four treads, each indicated broadly by thereference character A. Three risers B are employed for the three uppertreads. Each of the risers B is preferably in the form of a strip ofsheet metal presenting a vertical main web l2 and top and bottominwardly extended flanges l3-13- At each en'd, preferably integralrightangled flanges la are also provided to facilitate attachment of theriser to the stringere` as by rivets.

Each of the treads is of improved form, the details of which are bestshown in Figures :2 and 3. Each tread A, as shown, comprises a sheetmetal member having a bottom horizontal main portion 15, upwardlyextending front and rear integral flanges l6-l6, and top inwardly andhorizontally extended narrow edges 17-17 overhanging the bottom section15. It w'ill be noted that the flanges 16 and the bottom main web l5 areprovided with a relatively large number of holes or openings 18-18, thepurpose of which is explained hereinafter. Within the pan-shaped sheetmetal member above described and extending lengthwise thereof SerialN'o. 532,709.

`outwardly and horizontally extended as indicated at 21-21 so that thelatter overlie -but are spaced from the bottom portion l5.

The pan-shaped member with its anchoring element C is filled with anysuitable material adapted to assume a plastic form and which may bepoured therein while in plastic condition and thereafter allowed to set.Said filling, indicated at 2:2 may be of suitable compositionespecially' adapted to resist wear. Preferably the 1top surface of thefilling will be left slightly above the top surfaces of the inturnededges 1.7, as best shown in Figure 3.

By employing the anchoring element C, itwill be noted that the plasticmaterial will be caught under the flanges 2l and thereby securelyanchored to the pan-shaped tread member. Furthermore, the plasticfilling will be caught under the inturned edges l7-17 and within theanchoring openings 18 which are distributed throughout the pan-shapedtread member. Said openings 18, in addition to performing the anchoragefunction above mentioned, serve another important function in that theypermit of air and any moisture which may be trapped within the plasticcomposition during the pouring thereof, to get out through saidopenings. Furthermore, in the event water seeps into or around theplastic material and tends to expand or freeze in cold weather.I thesaid openings 18 permit the trapped water to pass out and also theplastic ma-.- terial to expand sufficiently to prevent distortion of thesheet meta-l pan-shaped tread element. Vith this arrangement, the treadmember of my improvements has long life and retains its essentialcharacteristics of strength and safety.

The treads are adapted to be secured to the stringers in any suitablemanner, as for instance by angle iron brackets 23 at each end of thetread.

I have herein shown and described what I now consider the preferredmanner of carrying out the invention, but the same is 11e merelyillustrative, and all changes and modifications are contemplated thatcome lsaid memberv and partially extended beneath said portions of saidanchoring element.

2. A tread for stairs comprising7 a panshaped sheet metal member havinga hori- Zonta] bottom portion and upwardly eX- tended front and rearanges; of a combined reinforcing and anchoring element secured to saidmember, said element being of substantially U-cross section with theside arms thereof extended outwardly approximately parallel to saidbottom portion; and

.a illing of plastic material within said member having portions thereofbeneath said flanges of the anchoring element.

3. A tread for stairs comprising7 a panshaped sheet metal member havinga hori- Zontal bottom portion, front and rear flanges, the latter havingtheir upper edges turned inwardly and over the bottom portion, saidsheet metal member being provided with a plurality of combinedVentilating and anchoring openings; a longitudinally extending anchoringelement secured to said horizontal bottom portion and having flangesabove and spaced from said bottom portion; and a filling of plasticmaterial wit-hin said member having portions thereof beneath saidflanges of the anchoring element and portions eXtended within saidopenings.

4f. A tread for stairs comprising, a panshaped metal member having ahorizontal bottom portion and upwardly extended front and rear flanges,the latter having their upper edges turned oppositely inwardly, saidbottom and said edge portions having a plurality 'ot' combinedVentilating and anchon ing openings therein; of a` combined reinforcingand anchoring element on the interior of said member extendinglengthwise thereof and secured to the bottom portion, said anchoringelement being of substantially U-shape with the sides thereof outwardlyYflared; and a filling of plastic material anchored beneath said elementand having portions thereof anchored also within said openings.

In witness that I cla-im the foregoing I have hereunto subscribed myname this 1 day of Jan., 1922.

WLL AM A. MTC HELL.

Witnesses W. S. CLARK, G. G. FAIRLEY.

